HowToPwn Achieves Top 10 in Industrial Intrusion CTF 2025

The Competition Overview

The Industrial Intrusion CTF 2025, hosted by TryHackMe, stands as one of the most prestigious cybersecurity competitions focusing on industrial control systems (ICS) and operational technology (OT) security. This year's competition drew over 500 teams from around the globe, making it the largest industrial cybersecurity CTF to date.

Our Journey to the Top

Our team's preparation began months before the competition. We focused on:

• Intensive training in ICS protocols
• Studying past industrial security incidents
• Practicing with similar environments
• Developing custom tools for ICS analysis

Key Challenges We Conquered

1. SCADA System Infiltration

One of the most challenging tasks involved exploiting vulnerabilities in a simulated SCADA system. Our approach included:

# Example of our custom Modbus protocol analyzer
def analyze_modbus_packet(packet):
    if packet[0] != 0x00:  # Unit identifier check
        return False
    
    function_code = packet[1]
    if function_code in [0x01, 0x02, 0x03, 0x04]:
        # Read coils/registers
        start_address = packet[2:4]
        quantity = packet[4:6]
        return validate_bounds(start_address, quantity)
                

2. PLC Firmware Analysis

We successfully reverse-engineered proprietary PLC firmware to identify potential vulnerabilities:

• Discovered hardcoded credentials
• Identified buffer overflow vulnerabilities
• Found backdoor communication channels

3. Protocol Fuzzing Challenge

Our team developed a custom fuzzing framework for industrial protocols:

class ICSFuzzer:
    def __init__(self, target_ip, target_port):
        self.target = (target_ip, target_port)
        self.protocols = ['modbus', 's7comm', 'dnp3']
    
    def fuzz_protocol(self, protocol):
        if protocol == 'modbus':
            return self._fuzz_modbus()
        elif protocol == 's7comm':
            return self._fuzz_s7comm()
                

Innovative Solutions

Our team's success was largely due to our innovative approaches:

1. Development of automated protocol analyzers
2. Custom-built ICS exploitation framework
3. Machine learning-based anomaly detection

Key Takeaways

This competition highlighted several critical aspects of industrial cybersecurity:

• The importance of understanding legacy systems
• The critical nature of protocol security
• The need for automated security testing tools
• The value of team collaboration and coordination

Looking Forward

Our achievement in the Industrial Intrusion CTF 2025 is just the beginning. We're already preparing for upcoming competitions and continuing to develop our skills in industrial cybersecurity. Stay tuned for more updates and detailed write-ups of our solutions!